System and method for multi-level vacuum generation and storage

ABSTRACT

A system and method for vacuum generation is disclosed. A saturated steam of higher than ambient pressure is inserted into a condensation cylinder with two chambers, separated by a movable piston, and wall-imbedded heat exchangers. The steam moves the piston to fill one chamber while expel gaseous content and condensate out of the other chamber. The steam is then condensed to a rough vacuum state by cooling. By repeated operations of inserting and condensing steam in each chamber alternatively, a sustained vacuum generation is achieved. A system and method for constructing a multi-level vacuum storage is also disclosed, with a high vacuum chamber placed inside a rough vacuum chamber to reduce the leakage as well as mechanical stresses. Furthermore the vacuum generation system and method is extended for creating a prime mover or actuator to drive vacuum pumps, maximizing the thermal energy usage for increased vacuuming capacity.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the benefit of the filing dates of U.S.Provisional Patent Application No. 62/347,670, filed Jun. 9, 2016, andU.S. Provisional Patent Application No. 62/393,142, filed Sep. 12, 2016,and U.S. Provisional Patent Application No. 62/396,313, filed Sep. 19,2016, the disclosures of which are hereby incorporated herein byreference.

FIELD OF THE DISCLOSURE

The present disclosure relates to a vacuum generation and storagesystem. In particular, the present disclosure relates to a dual-actionpiston-cylinder, multi-level vacuum generation system by wall-imbeddedcooling and/or atomized spray cooling, and a multi-level vacuum storagesystem.

BACKGROUND

Vacuum processing technology is used in a large number of generalindustrial applications. Current vacuum technology includes positivedisplacement pumps, momentum transfer pumps, entrapment pumps, andejectors to generate sub-atmospheric pressure at different vacuumlevels. Most of the current vacuum generation systems rely onelectricity and/or compressor as prime power source for producingmechanical movements in the systems. Each type of pumping mechanism hasdifferent characteristics in terms of the size and shape of volume tofill. However, the current vacuum technology lacks scalability that isnecessary for being used economically in large-scale open-flow systems.

It is very costly to generate sufficient removal flowrate for systemssuch as vacuum membrane separation for desalination or ground basedaltitude chambers that simulate cabin or cargo depressurization andreduced-pressure tubes that transport pods carrying passengers inhigh-speed transportation systems. U.S. Pat. No. 8,967,173 B2 to Lin etal. (the '173 Patent) describes the use of condensation of steam forreducing pressure in an enclosed volume. Cost savings on energyconsumption, and facility maintenance, are achieved since it is mucheasier to run a steam plant than to maintain a facility with largevacuum pumps. A significant issue, however, in the system and methoddisclosed in the '173 Patent is its dependence on the use of steam toflush gas, which has been previously extracted from a vacuum-neededapplication, out of the condensation chamber. During this process, newlyinserted steam first mixes with gas present in the condensation chamberand is flushed out as a mixture. Another drawback of the system in the'173 Patent is premature condensation also occurs during the mixing ofsteam with gas. As a result, a portion of the steam inserted into thecondensation chamber is lost and the condensation chamber is notcompletely filled with steam but a certain portion of non-condensablegas still remains. This amount of non-condensable gas residue cansignificantly affect the limit of vacuum achieved.

Vacuum storage and application chambers are all subject to permeationand leakage to some degree, which of course depend on the design of thechamber, the quality of the materials, the precision of the work, andvarious other factors. To attain or maintain the vacuum level, thevacuum generator must be capable of continuously evacuating thepermeation and leakage entering the system. The lower the pressure to bemaintained in the chamber, the higher the requirement to its tightness.This is because the expenditure for generating and maintaining vacuumincreases drastically with decreasing pressure. In general, to attain ormaintain the high vacuum level, the vacuum generator must be capable ofcontinuously evacuating the leakage entering the system. The associatedproblems are the high leakages and resultant high energy andinfrastructure costs.

As a result there is still a need in the art for a vacuum generation andstorage system that overcomes the drawbacks of the current systems.

SUMMARY

The present invention solves the problems of current state of the artand provides many more benefits. In accordance with embodiments of thepresent disclosure, a system and a method are disclosed for reducingpressure to a nearly vacuum state in an enclosed volume. In oneembodiment, water is inserted into a boiler to produce saturated steamof higher than atmospheric pressure. A first quantity of steam isinserted into the first chamber of two chambers separated by a movablepiston in an enclosed cylinder with wall-imbedded heat exchangers orsimilar heat transfer devices through the cylinder wall or endingplates. The first quantity of steam moves the piston to increase thevolume of the first chamber, reduce the volume of the second chamber andexpel gaseous content and condensates out of the second chamber. Thefirst quantity of steam is condensed to generate a depressurized ornearly vacuum state in the first chamber by the cooling of wall-imbeddedheat exchangers and/or atomized spray cooling from cylinder ends. Afirst quantity of gas is extracted from the depressurization-neededapplication system into the first chamber. A second quantity of steam isinserted into the second chamber in the enclosed cylinder. The secondquantity of steam moves the piston to increase the volume of the secondchamber, reduce the volume of the first chamber and expel gaseouscontent and condensates out of the first chamber. The second quantity ofsteam is then condensed to generate a depressurized or nearly vacuumstate in the second chamber by the cooling of wall-imbedded heatexchangers and/or atomized spray cooling from cylinder ends. A secondquantity of gas is extracted from the depressurization-neededapplication system into the second chamber. Then, these procedures aboveare repeated by inserting steam into the first chamber and so on.

The dual-chamber configuration in the dual-action piston-cylinder systemcombines filling steam in one chamber with expelling gas in the otherchamber. The separation of two chambers by the piston prevents the steamloss while ensuring a complete steam filling in the cylinder beforebeing subject to condensation, thereby providing significant cost savingon energy consumption due to more efficient use of steam. It should bepointed out that, should there be a minor leakage of steam over thepiston, the higher pressure on the steam-filling side ensures that theleakage direction is from the steam filling chamber to gas expellingchamber, which basically eliminates the possibility of havingnon-condensable gas in the steam-filling chamber.

In another embodiment, a dual-action piston-cylinder vacuum generationsystem comprises a condensation cylinder with channels along its wall, apiston with seal that forms two chambers of variable volumes inside thecondensation cylinder, a three-position closed-center steam valve, athree-position closed-center gas valve, a cold water valve, a steamgenerator, a water chiller as cold water supply, and an insulation layeroutside the cylinder wall to prevent heat exchange with the environment.The three-position closed-center steam valve is operable to receive afirst quantity of steam and insert it into the first chamber inside thecondensation cylinder. A piston is operable under the pressure of thefirst quantity of steam to increase the volume of the first chamber andreduce the volume of the second chamber expelling any condensate presentin the second chamber. A cold water valve is operable to receive andinsert the first quantity of cold water into the wall channels expellingany water present in the channels. The first quantity of cold watercondenses the first quantity of steam such that a vapor-to-liquid phasechange reduces pressure in the first chamber inside the condensationcylinder.

In an embodiment, a method for reducing pressure to a nearly vacuumstate in an enclosed volume includes inserting a first quantity of steaminto the first chamber and expelling the gas from the second chamber inthe condensation cylinder. The method further includes condensing thefirst quantity of the steam in the first chamber in the condensationcylinder by wall cooling and/or atomized spray cooling from cylinderends, then extracting a first quantity of gas from a vacuum-neededapplication into the first chamber in the condensation cylinder while,optionally, preheating the cylinder wall by inserting hot water into thewall channels. The method includes the steps of performing a secondaction of the cycle and inserting a second quantity of steam into thesecond chamber and expelling the gas from the first chamber in thecondensation cylinder, condensing the second quantity of the steam inthe second chamber in the condensation cylinder by wall cooling and/oratomized spray cooling from cylinder ends, and then extracting a secondquantity of gas from the vacuum-needed application into the secondchamber in the condensation cylinder while, optionally, preheating thecylinder wall by inserting hot water into the wall channels.

The steam used in the process could be the waste steam, or produced withwaste heat, from some processing industries or any other heating sourcesincluding solar or geothermal energy, or produced in a boiler with lowquality energy. In this manner, embodiments of the present disclosureprovide systems and methods of vacuum generation with the energy-saving,portability and scalability that are hard to achieve with theelectricity powered vacuum pumps. The systems of the present disclosurecan operate at low- or non-pressurized conditions and use low-heatenergies, hence much safer and more economically viable, compared tothose pressurized or high-temperature vacuum technologies.

In one embodiment, atomized spray nozzles are provided to expedite thecondensation process. The spray nozzles serve to cool the inside of thechambers. Alternatively, other suitable wall cooling devices could beemployed.

The leakage rate in a vacuum chamber is proportional to the pressuredifference inside and outside of the vacuum chamber. It is much moreexpensive to remove gas from a high-vacuum chamber than from arough-vacuum chamber or application chamber. In accordance withembodiments of the present disclosure, a high vacuum (HV) chamber isplaced inside a rough vacuum (RV) chamber to reduce the pressuredifference across the HV chamber walls. The resulting multi-level vacuumstorage reduces the leakage entering the high vacuum chamber andevacuates more leakage entering the rough vacuum chamber, therebyreducing energy costs for attaining and maintaining the high vacuumlevel. In addition, the much reduced pressure difference between RV andHV chambers leads to a great reduction in mechanical stresses over theHV chamber and hence reduces the material requirement and cost of the HVchamber.

In accordance with embodiments of the present disclosure, another systemand method are disclosed to create a prime mover or actuator with adual-action piston-cylinder vacuum generation system to drive vacuumpumps, instead of evacuating a vacuum chamber directly. After the firstchamber of a dual-action piston-cylinder condensation cylinder isdepressurized to a nearly vacuum state with the method disclosed above,a second quantity of steam is inserted into the second chamber. Thepressure of the second quantity of steam, together with the rough vacuumin the first chamber, moves the piston and the rod connected to thepiston in one direction. The rod then drives one or more vacuum pumps toevacuate gas from the HV and/or RV chambers. At the end of the pistonstroke, the condensate in the first chamber is expelled out of thechamber and is recycled. Then the second action of the cycle starts bycondensing the second quantity of steam in the second chamber togenerate a depressurized or rough vacuum state through the cooling ofchamber wall by using wall-imbedded heat exchangers and/or through theatomized spray cooling from cylinder ends. The pressure of the steam,together with the rough vacuum in the second chamber, moves the pistonand the rod connected to the piston in the other direction. The rod thenmoves the pistons of two or more vacuum pumps to evacuate gas from theHV and/or RV chambers. At the end of the piston stroke, the condensatein the second chamber is expelled out of the chamber and is recycled.The above procedures are repeated by inserting and condensing steamalternatively in the two chambers of the condensation cylinder. Thedual-chamber configuration in the dual-action piston-cylinder systemcombines the pressure of steam on one side of the piston with roughvacuum, produced through condensation, on the other side of the pistonto produce actuation power. The condensation cylinder is now a RVactuator, instead of a RV generator, which can be used to drive othermechanical devices including HV pumps. One particular advantages of thisarrangement is the separation of the operational environment of thedual-piston dual-action cylinder from the operational environment of themechanical devices powered by the dual-piston dual-action cylinder. Forinstance, the working substance of the dual-piston dual-action cylinderis steam and its condensates, while the powered devices (such as HVpumps) can work under different pressure and temperature with othersubstances. Another particular advantage of this arrangement is thebetter use of the thermal energy of the steam for more useful work.

In this manner, embodiments of the present disclosure provide a designof a scalable, environmentally friendly, safer, waste-heat utilizableand low-energy consumption system for rough and high vacuum generationand storage. The linear motion of the RV actuator may be convertedthrough a gear mechanism into linear motion of other stroke length todrive liner pumps or into rotary motion to drive rotary pumps. Muchreduced use of electricity and efficient use of steam providesignificant cost saving on energy consumption in generating high vacuum,which also greatly improves the portability of the system.

In another embodiment, a dual-action piston-cylinder rough vacuumgeneration system comprises, in addition to the dual-actionpiston-cylinder vacuum generation system, a compression cylinder, apiston with seal that forms two chambers of variable volumes inside thecompression cylinder, a three-position closed-center valve connected viapipe to the RV chamber, and a three-position closed-center valveconnected via pipe to ambient or a recycling facility. Thethree-position closed-center RV valve is operable to receive a firstquantity of gas from the RV chamber and insert it into the first chamberinside the compression cylinder. A piston is operable by the pistonmovement of the dual-action piston-cylinder vacuum generator to increasethe volume of the first chamber and reduce the volume of the secondchamber expelling gas present in the second chamber into the ambient ora recycling facility. The piston is then operable by the piston movementof the dual-action piston-cylinder vacuum generator to decrease thevolume of the first chamber expelling gas present in the first chamberinto the ambient or a recycling facility, and increase the volume of thesecond chamber receiving a second quantity of gas from the RV chamberthrough the three-position closed-center RV valve. This dual-actioncycle repeats to reduce the pressure in the RV chamber.

In another embodiment, a dual-action piston-cylinder high vacuumgeneration system comprises a compression cylinder, a piston with sealthat forms two chambers of variable volumes inside the compressioncylinder, a three-position closed-center valve connected via pipe to theHV chamber, and a three-position closed-center valve connected via pipeto the RV chamber or ambient or a recycling facility. The three-positionclosed-center HV valve is operable to receive a first quantity of gasfrom the high vacuum chamber and insert it into the first chamber insidethe compression cylinder. A piston is operable by the piston movement ofthe dual-action piston-cylinder vacuum generator to increase the volumeof the first chamber and reduce the volume of the second chamberexpelling gas present in the second chamber into the RV chamber throughthe three-position closed-center RV valve. The piston is then operableby the piston movement of the dual-action piston-cylinder vacuumgenerator to decrease the volume of the first chamber expelling gaspresent in the first chamber into the rough vacuum chamber through thethree-position closed-center RV valve, and increase the volume of thesecond chamber receiving a second quantity of gas from the HV chamberthrough the three-position closed-center HV valve. This dual-actioncycle repeats to reduce the pressure in the HV chamber.

Embodiments of the present disclosure are related to generate a lowpressure environment, from sub-atmospheric pressure to near-vacuum, inenclosed large-scale volumes or open-flow systems. More particularly,embodiments of the present disclosure are related to evacuating gas andvapor in vacuum-assisted applications such as wastewater treatments, seawater desalination, petroleum refining, vapor deposition, vacuumcleaning, aerosol filtration, and vacuum-assisted pneumatic conveying.Embodiments of the present disclosure are also related to ground basedaltitude chambers that simulate cabin or cargo depressurization, andreduced-pressure tubes that transport pods carrying passengers inhigh-speed transportation systems.

Any combination and/or permutation of the embodiments are envisioned.This summary is not intended to identify key or essential features ofthe claimed subject matter, nor is it intended to be used as aid indetermining the scope of the claimed subject matter. Other objects andfeatures will become apparent from the following detailed descriptionconsidered in conjunction with the accompanying drawings. It is to beunderstood, however, that the drawings are designed as an illustrationonly and not as a definition of the limits of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of embodiments of the present disclosuremay be derived by referring to the detailed description and claims whenconsidered in conjunction with the following figures. The figures areprovided to facilitate understanding of the disclosure without limitingthe breadth, scope, scale, or applicability of the disclosure. Thedrawings are not necessarily made to scale.

FIG. 1 is an illustration of an exemplary functional block diagram of adual-action piston-cylinder rough vacuum (RV) generation systemaccording to an embodiment of the present disclosure;

FIG. 2 is an illustration of an exemplary simulation of dual-actionpiston-cylinder vacuum generation system showing the system in FIG. 1;

FIGS. 3A-3B are block diagrams illustrating an exemplary flowchartshowing a dual-action cycle for an enclosed volume vacuum generationprocess;

FIGS. 4A, 4B, and 4C are illustrations of exemplary variations ofpiston-cylinder configurations according to the present disclosure;

FIGS. 5A, 5B, 5C are an illustration of an exemplary cross-section viewof the second variation of a piston-cylinder shown in FIG. 4A, and anillustration of two exemplary shapes of heat exchange channels in thecylinder wall;

FIG. 6 is an illustration of an exemplary continuous operation involvinga cascade condensation chamber system;

FIG. 7 is an illustration of a condensation cylinder with atomizingspray nozzles for enhanced cooling condensation and an exemplaryarrangement with atomizing spray nozzles for enhanced coolingcondensation inside the cylinder chambers;

FIG. 8 is an illustration of an exemplary functional block diagram of aDual-Action Piston-Cylinder Rough Vacuum Actuation and High VacuumGeneration System according to the present disclosure;

FIG. 9 is an illustration of an exemplary multi-level vacuum storage andapplication according to the present disclosure; and

FIG. 10 is an illustration of an exemplary axial arrangement ofcondensation cylinder, condensation-based actuator, and compressioncylinders for rough and high vacuum generation (only one pump is shown)according to the present disclosure.

DETAILED DESCRIPTION

The following detailed description is exemplary in nature and is notintended to limit the present disclosure or the application and uses ofthe embodiments of the present disclosure. Descriptions of specificdevices, techniques, and applications are provided only as examples.Modifications to the examples described herein will be readily apparentto those of ordinary skill in the art, and the general principlesdefined herein may be applied to other examples and applications withoutdeparting from the spirit and scope of the disclosure. The presentdisclosure should be accorded scope consistent with the claims, and notlimited to the examples described and shown herein.

Embodiments of the disclosure may be described herein in terms offunctional and/or logical block components and various processing steps.It should be appreciated that such block components may be realized byany number of hardware, software, and/or firmware components configuredto perform the specified functions. For the sake of brevity,conventional techniques and components related to vacuum generationtechniques, steam plants, pressure regulators, ducting systems, controlsystems, and other functional aspects of the systems (and the individualoperating components of the systems) may not be described in detailherein. In addition, those skilled in the art will appreciate thatembodiments of the present disclosure may be practiced in conjunctionwith a variety of structural bodies, and that the embodiments describedherein are merely example embodiments of the present disclosure.

Embodiments of the present disclosure are described herein in thecontext of practical non-limiting application, namely, a rough vacuumgeneration system, and a multi-level vacuum generation system poweredwith a rough vacuum generation and actuation system. Embodiments of thedisclosure and the techniques described herein, however, may be utilizedin various vacuum applications 140. For example, but without limitation,embodiments may be applicable to a vacuum-assisted device for wastewatertreatments, sea water desalination, petroleum refining, vapordeposition, vacuum cleaning, aerosol filtration, vacuum-assistedpneumatic conveying, a ground based altitude chamber for aircraft cabinor cargo depressurization simulation, and reduced-pressure tubes thattransport pods carrying passengers in high-speed transportation systems.

One application involves wastewater treatment technology. Industrialwastewater from chemicals industry, electric power plants, nuclearindustry, agricultural and food operations, iron and steel industry, andhydraulic fracturing, etc. must be treated to reduce their damage to theenvironment. Vacuum evaporation and distillation can lead to a dramaticreduction in the volume of liquid waste to make it easier to treateffluents.

Another application involves desalination technology. More than one inevery six people in the world does not have access to potable water. Twoconverging phenomena drive water scarcity: growing freshwater use anddepletion of usable freshwater resources. Desalination of sea water isalready common in arid areas of the world. Vacuum Membrane Distillation(VMD) is becoming a viable process for desalination.

Another application involves high-volume aerosol filtration technology.A high efficient aerosol filtration system, such as High-EfficiencyParticulate Arrestance (HEPA) filter for removal of ultrafineparticulates such as PM2.5 (particulate matter less than 2.5 micrometersin diameter), typically requires a high pressure head to overcome thehigh pressure drop that increases in a quadratic function with theincrease in flowrate. This disclosed vacuum technology provides an idealflow driving solution, which is of low energy cost and low noise, whilegenerating high pressure difference to meet the ever-growing needs offiltrations of ultrafine aerosols.

Another application involves high-speed transportation systems(hyperloop). A conceptual high-speed transportation system incorporatesreduced-pressure tubes in which pressurized capsules ride on an aircushion driven by linear induction motors and air compressors.Preliminary analysis indicates that such a route may obtain an averagespeed of around 600 mph (970 km/h), with a top speed of 760 mph (1,200km/h). Such systems will rely on efficient and continuous vacuumgeneration as a critical component due to its incorporation ofreduced-pressure tubes.

As would be apparent to one of ordinary skill in the art after readingthis description, the following are examples and embodiments of thepresent disclosure and are not limited to operating in accordance withthese examples. Other embodiments may be utilized and structural changesmay be made without departing from the scope of the exemplaryembodiments of the present disclosure.

Existing systems for vacuum processing technology typically are noisydue to a mechanism used to extract gas from a vacuum-needed application.Also it is very costly to apply these existing systems to very largeenclosed volumes due to the energy consumption for such a facility.

Embodiments of the disclosure solve this problem by generating roughvacuum by condensing steam with a more efficient system and method, andthen by actuating vacuum pumps with power from the pressure of the roughvacuum and steam. For an even wider application, the system and methoddescribed herein can be used in high-speed transportation systemdevelopment around the world, such as the high speed rails or the use ofreduced-pressure tubes that transport pods carrying passengers in ahyperloop. Therefore, testing and/or operating at high speed in anenclosed tunnel or tube under lower pressure is necessary to reduce dragand noise and would enable more efficient operation. Embodiments of thedisclosure provide viable means for depressurizing an enclosed tunnel ortube with low energy consumption.

Embodiments of the disclosure apply phase change to producedepressurization to a rough vacuum state in an enclosed volume 130.Embodiments of the disclosure also apply the rough vacuum and steam asefficient actuation power for driving vacuum pumps. Furthermore,embodiments of the disclosure apply multi-level vacuum storage to reducethe energy costs for attaining and maintaining the vacuum level.

FIG. 1 is an illustration of an exemplary functional block diagram of adual-action piston-cylinder rough vacuum generation system 100 accordingto an embodiment of the present disclosure. The system 100 could includea steam generator, a plurality of condensation piston-cylinders ofsufficient thermal conduction comprising channels in the cylinder wallsand/or a plurality of atomizing spray nozzles, a piston of sufficientthermal insulation coupled with a seal in each of the condensationpiston-cylinders, ra three-position closed-center steam valve (or a pairof two-way steam valves), a plurality of compression piston-cylinders,and a system controller 110 that operates the valves through itsinteractions with two sets of position, pressure and temperature sensorsinstalled on each of the condensation piston-cylinder. It will beunderstood that the number of piston-cylinders could vary. An optionalwater chiller 120 could be used to ensure the temperature of the coldwater for inducing condensation is sufficiently low for the desiredvacuum level. When the dual-action piston-cylinder rough vacuumgeneration system is to be used as a prime mover or actuator, hot watercould be supplied from the steam generator to prevent any potentialpremature condensation of steam by repelling cold water from coolingchannels and heating the piston-cylinders before and duringsteam-filling.

The rough vacuum generation system could include subsystems andcomponents to measure and control process variables, such as pressureand temperature, as required for effective performance. The controller110 could receive at least one process parameter, process the at leastone process parameter, and adjust operation of the system based uponprocessing of the at least one process parameter.

In the first action, a steam valve 116 is opened to allow the firstquantity of steam, typically at an elevated pressure above atmosphericpressure, to flow into one of the two chambers in each of a plurality ofcondensation cylinders 118. The condensation cylinders 118 couldinclude, for example, condensation cylinders 1 to N, where N is aninteger. The number N can be any number greater than or equal to one.The number N may be chosen based on, for example, but withoutlimitation, a flow rate control, a condensation cylinder cost, and anenergy use (e.g., few large cylinders may use less energy). Thecontroller 110 detects the completion of the steam filling, based on theposition of the piston, or the pressure and the temperature in the firstchambers, and moves the steam valve accordingly to the center positionto stop the flow of the first quantity of the steam.

A cold water valve 119 opens to allow the first quantity of the coldwater into wall channels of the condensation cylinders and expel anywater present in the channels, and/or into the chamber through atomizingspray nozzles. The first quantity of cold water reduces a temperature inthe condensation cylinders and condensates the saturated steam intowater. For example, but without limitation, the temperature on thecondensation surface could be reduced from about 105° C. to about 15° C.In this example, the steam condensation into water reduces the pressureinside the first chambers in the condensation cylinders to a roughvacuum state.

The controller 110 detects the lower pressure in the first chambers andmoves a three-position gas valve 122 accordingly to the first positionto allow the first quantity of the gas to flow to the first chambers,thereby depressurizing the target vacuum-needed application system to adesired pressure or sub-atmospheric pressure.

The controller 110 detects the completion of the drawing gas from thevacuum-needed application and moves the three-position gas valve 122 tothe center position accordingly to stop the flow of the first quantityof gas into the first chambers.

The controller 110 detects the proper cylinder temperature and moves thesteam valve 116 accordingly to the second position to allow the secondquantity of the steam to flow into the second chambers in each of thecondensation cylinders. The pressure of the steam fills the secondchambers and moves the pistons and expels the gas previously flowed intothe first chambers and any condensates in the first chambers.

The controller detects the completion of the steam filling and moves thesteam valve to the center position to stop the flow of the secondquantity of the steam. The cold water valve 119 opens again to allow thecold water into the wall channels, and/or into the chamber through theatomizing spray nuzzles, of the condensation cylinders to reduce atemperature in the condensation cylinders by condensing the saturatedsteam into water. Changing the steam to water reduces a pressure insidethe second chambers in the condensation cylinders to a pressure lowerthan that in the vacuum-needed application 140 such that the gas canflow into the second chambers.

The controller 110 detects the pressure below a designed value in thesecond chambers and moves three-position gas valve 122 accordingly tothe second position to allow the gas to flow into the second chambers,thereby depressurizing the target vacuum-needed application system to adesired pressure or sub-atmospheric pressure.

During operation, all the water flowing through the wall channels of thecylinders when heating or cooling the cylinders is recycled to a steamand hot water generator 115.

A single cylinder system does not provide continuous vacuum operations,due to the short transition time needed to depressurize the chamberduring the two actions. Additional identical cylinders should be used ifa continuous vacuum operation is desired. For dual-cylinder ormultiple-cylinder systems, properly arranged delay in starting theoperation of each cylinder is required to ensure at least one cylinderis ready to provide vacuum at any time. Alternatively, a vacuum-bufferchamber can be used to sustain a continued vacuum suction operation.

FIG. 2 is an illustration of an exemplary dual-action piston-cylindervacuum generation system 200 in more detail according to an embodimentof the disclosure. The system could comprise the enclosed volume 130, aboiler 210 for steam and hot water generation, a plurality ofcondensation piston-cylinders 220 comprising channels 222 in thecylinder walls, a water chiller 230 for cold water, a hot waterreservoir 232, a three-position closed-center gas valve 240, athree-position closed-center steam valve 242, two gas valves 244, and acontroller 110 that operates the valves through its interactions withtwo sets of position sensor S, pressure sensor P and temperature sensorsT1 and T2 installed on each of the condensation piston-cylinders, andtemperature sensor T embedded in the cylinder wall close to thecondensation surface. The configuration of the dual-actionpiston-cylinder illustrated in this FIG. 2 is the variation 1 amongseveral other conceivable variations.

The enclosed volume 130, functioned as a vacuum storage, is coupled tothe three-position closed-center gas valve 240. The enclosed volume 130draws the gas from the application which utilizes the vacuum orextremely-low sub-atmospheric pressure of the enclosed volume when valve241 coupled to the application is opened. The gas is then extracted fromthe application through the three-position closed-center gas valve toprovide a reduced pressure in the application. The gas then flowsalternately through respective gas ducts to the respective chambers whenthe three-position closed-center gas valve is in its first and secondposition respectively.

The three-position closed-center gas valve between the enclosed volumeand the chambers of the condensation cylinders opens to the respectivegas ducts to allow the gas in the enclosed volume to be drawnalternately into the two chambers 221, 223 in each of the condensationcylinders 220 respectively based on respective pressure in the chambersof the condensation cylinders.

In this manner, the three-position closed-center steam valve moves tothe first position to allow a first steam flow of a first quantity ofthe steam into the first chambers 221 of the condensation cylinders,moves to the second position to allow a second steam flow of a secondquantity of the steam into the second chambers 223 of the condensationcylinders, and moves to a center position to block a first or secondsteam flow into the two chambers of the condensation cylinders.

Each of the two chambers is operable to receive the steam from theboiler 210 and extract the gas from the enclosed volume alternately. Inoperation, the first chamber could begin to be filled with the steam andincrease in volume, while the second chamber reduces its volume andexpels any gas present though an outlet. The first chamber 221 begins tocondense the first quantity of the steam and extracts the first quantityof the gas from the enclosed volume into the first chamber. Once thefirst chamber is filled with the first quantity of the gas, thethree-position closed-center gas valve 240 moves to the center positionto stop the flow of the first quantity of the gas from the enclosedvolume into the first chamber. The second chamber 223 is filled by thesecond quantity of the steam, condenses the second quantity of steam,and begins to receive the second quantity of the gas. In this manner,the flow of the gas is alternated between the two chambers until adesired depressurization is obtained in the enclosed volume.

Water condensate and gas could exit from an outlet 250 in each chamberrespectively. For example, the first quantity of the gas from the firstchamber is substantially expelled during the flow of the second quantityof the steam.

The cold water is operable to condense the steam such that avapor-to-liquid phase change reduces a pressure in the two chambers ofcondensation cylinders. The embodiment in FIG. 2 shows one condensationcylinder, but any number of additional condensation cylinders could beused to obtain the required pressure in the enclosed volume. The steamand hot water generator generates the steam at temperatures such as, forexample, but without limitation, about 105° C. The steam and hot watergenerator also generates hot water at, for example, close to 100° C.

The steam is then cooled down by the cold water. The water chillerprovides the cold water through a duct to the wall channels in each ofthe cylinders. The cold water could come from a chiller at a regulartemperature such as, for example, but without limitation, about 15° C.

The controller 110 comprises a processor module 201, a memory module202, and connection wires to all the sensors and valve actuators. Thecontroller is operable to control the three-position closed-center gasvalve between the enclosed volume and the two chambers to allow the gasin the enclosed volume be drawn to the chambers alternately. Thecontroller is operable to control the three-position closed-center steamvalve between the steam generator and the two chambers to allow thesteam to enter the chambers alternately. The controller is operable tocontrol a hot water valve 233 and a cold water valve 234 and/or a threeway valve 235 to allow the hot or cold water to flow into the wallchannels of the cylinders to heat or cool the cylinders alternately. Thecontroller is operable to control outlet valves to allow gas and watercondensate to exit the chambers during steam fillings.

The processor module comprises processing logic that is configured tocarry out the functions, techniques, and processing tasks associatedwith the operation of the systems. In particular, the processing logicis configured to support the systems described herein. For example, theprocessor module could direct the three-position closed-center steamvalve to alternate the flow of the steam from the steam generator to thechambers. For another example the processor module could direct thethree-position closed-center gas valve to alternate the flow of the gasbetween the two chambers based on the pressure in the two chambers.

The processor module could be implemented, or realized, with a generalpurpose processor, a content addressable memory, a digital signalprocessor, an application specific integrated circuit, a fieldprogrammable gate array, any suitable programmable logic devices,discrete gates or transistor logic, discrete hardware components, or anycombination thereof, designed to perform the functions described herein.In this manner, a processor may be realized as a microprocessor, acontroller, a microcontroller, a state machine, or the like. A processormay also be implemented as a combination of computing devices, e.g., acombination of a digital signal processor and a microprocessor, aplurality of microprocessors, one or more microprocessors in conjunctionwith a digital signal processor core, or any other such configuration.

The memory module could comprise a data storage area with memoryformatted to support the operation of the systems. The memory module isconfigured to store, maintain, and provide data as needed to support thefunctionality of the system. For example, the memory module could storea database, a temperature database, an operational control data, andflight configuration data.

In practical embodiments, the memory module could comprise, for example,but without limitation, a non-volatile storage device (non-volatilesemiconductor memory, hard disk device, optical disk device), a randomaccess storage device (for example, SRAM, DRAM), or any other form ofstorage medium known in the art.

The memory module could be coupled to the processor module andconfigured to store, for example, but without limitation, a database, atemperature database, and an operational control data. Additionally, thememory module may represent a dynamically updating database containing atable for updating the database, and the like. The memory module couldalso store, a computer program that is executed by the processor module,an operating system, an application program, tentative data used inexecuting a program, and the like. The memory module could be coupled tothe processor module such that the processor module can read informationfrom and write information to the memory module.

As an example, the processor module and memory module could reside inrespective application specific integrated circuits (ASICs). The memorymodule could also be integrated into the processor module. In anembodiment, the memory module could comprise a cache memory for storingtemporary variables or other intermediate information during executionof instructions to be executed by the processor module.

FIG. 3 is an illustration of an exemplary flowchart showing an enclosedvolume vacuum generation process according to an embodiment of thedisclosure. The various tasks performed in connection with the processcould be performed mechanically, by software, hardware, firmware, acomputer-readable medium having computer executable instructions forperforming the processes methods, or any combination thereof. The tasksin the flowchart include an optional use of hot water 117 forpre-heating the cylinder during steam-filling. It should be appreciatedthat the process could include any number of additional or alternativetasks, the tasks shown in FIG. 3 need not be performed in theillustrated order, and the process could be incorporated into a morecomprehensive procedure or process having additional functionality notdescribed in detail herein. For illustrative purposes, the followingdescription of the process could refer to elements mentioned above inconnection with FIGS. 1 and 2.

In practical embodiments, portions of the process could be performed bydifferent elements of the systems such as: the enclosed volume, thesteam and hot water generator, the two chambers in the condensationcylinder, the coolant supply or chiller, the three-positionclosed-center gas valve, the three-position closed-center steam valve,and the like. The process could have functions, material, and structuresthat are similar to the embodiments shown in FIGS. 1 and 2. Therefore,common features, functions, and elements may not be redundantlydescribed here.

Depending on the implementation, the process begins as shown in block310 with a first action by inserting a first quantity of the steam intothe first chamber (task 1).

The process continues as shown in block 320 by moving the piston insidethe condensation cylinder to increase the volume of the first chamberand expelling the gas and water condensate from the second chamber (task2).

Block 330 shows the process may continue by blocking the steam flow intothe first chamber (task 3).

Next block 340 shows the process could continue by opening the coldwater valve to cool the cylinder walls (task 4).

Block 350 shows the process could continue by condensing substantiallythe first quantity of the steam in the first chamber (task 5). The firstquantity of the steam could be cooled, for example, but withoutlimitation, from about 105° C. to about 15° C. Based on energy balance,a total enthalpy difference of the saturated steam at about 105° C. tothat at about 15° C. can be obtained to determine an amount of the heatthat needs to be removed.

Block 360 shows the process could then continue by moving the gas valveand extracting a first quantity of the gas from an enclosed volume intothe first chamber (task 6).

Block 370 shows the process could continue by blocking the gas flow intothe first chamber (task 7).

Block 380 shows the process could then continue by closing the coldwater valve and, optionally, opening the hot water valve to heat thecylinder walls (task 8). The first action completes and the secondaction begins in the next task.

Block 390 shows the process could then continue by inserting a secondquantity of the steam into the second chamber (task 9).

Block 391 shows the process could then continue by moving the pistoninside the condensation cylinder to increase the volume of the secondchamber and expelling the gas and water condensate from the firstchamber (task 10).

Block 392 shows the process could then continue by blocking the steamflow into the second chamber (task 11).

Block 393 shows the process could then continue by closing the hot watervalve, if hot water valve is opened when performing task 8, and openingthe cold water valve to cool the cylinder walls (task 12).

Block 394 shows the process could then continue by condensingsubstantially the second quantity of the steam in the second chamber(task 13).

Block 395 shows the process could then continue by moving the gas valveand extracting a second quantity of the gas from an enclosed volume intothe second chamber (task 14).

Block 396 shows the process could then continue by blocking the gas flowinto the second chamber (task 15).

Block 397 The process could then continue by closing the cold watervalve and, optionally, opening the hot water valve to heat the cylinderwalls (task 16). As the second action completes, the cycle ofdual-action completes as shown in the completion at Block 398.

FIGS. 4A, 4B, and 4C are illustrations of exemplary additionalvariations of the embodiments of piston-cylinder configurations, withthe embodiment in FIG. 2 as the first variation. The first variationuses a rodless piston whose movement inside the cylinder is caused bythe pressurized steam (steam at elevated temperature), without anymechanical interactions with external mechanisms.

The second variation shown in FIG. 4A also uses a rodless piston 401,but one (or more) hollow shaft 402 is added to the inside of thecylinder along its axis. When only one shaft is used in this embodiment,however more may be disposed about the axis depending on theimplementation. The shaft is to be placed at the center of the cylinderas shown in the FIG. 4A. This hollow shaft provides additionalstructural support and guide for the piston and is to be used togetherwith the channels 403 in the cylinder wall for additional heating andcooling the cylinder. The rodless piston in this variation has a centralhole 405 and an accompanied seal 406 for moving along the central shaft402.

The third variation as shown in FIG. 4B uses a piston 410 with a rod 411attached to one side. As in the first variation, the pressurized steamis used to move the piston 410 inside the cylinder 412. With thisvariation, the piston rod 411 is used to interact with externalmechanism when a dual-action piston-cylinder system is used as a primemover or actuator. Due to the non-symmetric configuration, the twochambers (A&B) 413 and 414 respectively have slightly different volumesand operation parameters for the two chambers need to be adjustedaccordingly.

The fourth variation shown in FIG. 4C uses a piston 420 with rods 421,422 attached to both sides. The fourth variation works in the same wayas the third variation, but with support at both ends, both thethickness of the piston and diameter of rods can be reduced to increasethe volume in both chambers 423, 424 for the same cylinder. Thisvariation provides a symmetric configuration such as the same operationparameters could be used for both chambers.

Variations 3 and 4 transfer some thermodynamic energy, generated bycondensation-induced vacuum, back into mechanical work that otherwisemay be lost during the simple vacuum suction such as in Variations 1 and2. Variations 1 and 2 represent the no-load applications of the piston,while load is applied to piston in variations 3 and 4. Higher tightnessof the seals is needed for variations 3 and 4, compared with the no-loadconfiguration. While the tighter seal adds friction to the piston,variations 3 and 4 could still provide much better vacuuming capacitiesthan those from variations 1 and 2.

FIGS. 5A, 5B, 5C are an illustration of an exemplary cross-section viewof the second variation of the piston-cylinder. FIGS. 5B, 5C alsoprovides an illustration of two exemplary channel shapes 520, 530respectively in the cylinder wall 510. It will be understood that otherchannel shapes could be employed for better mechanical structure,material saving, and/or energy transfer.

FIG. 6 is an illustration of an exemplary continuous operation involvinga cascade condensation chamber system 600 or an integratedcondensation-buffer chamber system. In this example, three condensationchambers 610, 620, 630 are used, however depending on the implementationtwo or more condensation chamber may be used in this system 600.

FIG. 7 is an illustration of an exemplary arrangement with atomizingspray nozzles 710. A cylinder 700 can be cooled by an atomized spray ofwater into its chambers 712, 714, for example, with piston 720 retractedinto chamber 714 in this example. This spray nozzles are in addition tothe cooling through the wall-embedded channels 222 within the cylinderwalls 716. Insulation 718 may be used in cylinder 700 as in the otherembodiments to contain thermal and cooling energies within the cylinder700. The injection of atomized fine droplets provides a large surfaceexposure for additional heat transfer and condensation, as well asenhanced condensation thermal capacity and prolonged contact time forphase changes. While FIG. 7 shows four spray nozzles, it will beunderstood that the number of spray nozzles could vary.

FIG. 8 is an illustration of an exemplary functional block diagram of adual-action piston-cylinder for condensation-based actuation andrough/high vacuum generation system 800. The system could include thesame components and work in the same way as discussed in the previousfigures for rough vacuum generation, except that some of thecondensation cylinders are configured as the variations 3 or 4 in FIGS.4B, and 4C. The rough vacuum 810 is now used to work together with thesteam to move the piston rod 820. The reciprocating linear motion of thepiston rod can then drive a linear or rotary compression cylinders(vacuum pumps) 830 through an external rack and pinion mechanism. Thoseexternal vacuum pumps can be used to generation or maintain high vacuumin targeted applications. When a condensation cylinder is used as anactuator, the movement speed of the piston will be reduced due to theload applied on the piston rod by the vacuum pumps that it is coupledwith. Therefore the piston seal needs to be tighter, compared with theno-load configuration. Preheating of the cylinder wall beforesteam-filling might be necessary to minimize the pre-maturedcondensation of steam during the steam-filling.

FIG. 9 is an illustration of an exemplary multi-level vacuum storage andapplication 900 according to an embodiment of the present disclosure.The system could comprise two or more enclosed volumes 910 and 920having a pressure “P” the same or different depending on theimplementation, and functioned as rough and high vacuum storages for therough vacuum and the high vacuum generated by the compression cylinders.A multi-level vacuum storage reduces overall energy cost of attainingand maintaining the high vacuum in the enclosed volume. In addition, thereduced pressure difference between two neighboring multi-level chambersleads to the reduction in mechanical stresses over their chamber wallsand hence reduces the material requirement and cost of each chamber.Each of the enclosed vacuum volumes is connected to the compressioncylinders through ducts and control valves for attaining and maintainingthe vacuum level.

FIG. 10 is an illustration of an exemplary piston-cylindercondensation-based linear actuator system 1000 for rough and high vacuumgeneration. The driving force of the linear actuator is proportional tothe pressure difference between the feeding steam on one side and roughvacuum on the other side of the pistons as well as to thecross-sectional area of pistons. Only an exemplary axial arrangement ofcondensation cylinder (i.e., condensation-based actuator) andcompression cylinders is shown in this example. Other embodiments mayapply to this system. The stroke distance of the compression cylinder1010 can be different from that of the condensation cylinder 1020through a gear mechanism. One variation to the axial arrangement ofcondensation cylinder and compression cylinders may include parallelarrangement with compression cylinders placed around the condensationcylinder. Another variation is to mechanically convert the linear motionof the rod into rotary motion of a crank through rack and pinion. Therotation of the crank drives other reciprocating pumps such as pistonpumps or diaphragm pumps. A speed multiplying gearing set is then usedto produce higher speed rotation for driving reciprocating pumps throughin-line crank-slider mechanism. For maintaining continuing smoothoperation of the pumps when the piston and rack reverse directions, thecorresponding position of the crank should be designed to produce atransmission angle near 90° in the crank-slider mechanism, when thepiston and rack change their direction of motion. Two exemplary options,A and B, for interacting with a multilevel vacuum storage is shown inthe FIG. 10. In option A, the gaseous content evacuated by thecompression cylinder from the RV chamber could be pushed into ambient orrecycling facility directly. In option B, the gaseous content evacuatedby the compression cylinder from the HV chamber could be pushed into theRV chamber, for reducing the pressure difference between the two sidesof the piston in the compression cylinder, instead of being pusheddirectly into ambient or recycling facility.

The rod 1030 of the condensation cylinder in FIG. 10 could bemechanically coupled to a plurality of compression cylinders orreciprocating pumps, for example, pumps 1 to M, where M is an integer.The number M can be any number greater than or equal to one. The numberM may be chosen based on, for example, but without limitation, a flowrate control, a compression cylinder cost, the pressure in the vacuumchambers, and the steam pressure for moving the piston of thecondensation cylinder. The rod of the condensation cylinder can beindividually coupled or decoupled to the compression cylinders withcontrollable mechanical couplings. The controller selects a number ofcompression cylinders for rough vacuum generation and another number ofpumps for high vacuum generation according to the specific needs. Thetotal number pumps selected for each operation cycle can be less than orequal to M.

The controller coordinates the movements of the pistons in thecompression cylinders in FIG. 10 by controlling the valves to allow thefirst quantity of the gas in the corresponding vacuum chambers to flowinto the first chambers in each of the compression cylinders. The outletvalves are controlled simultaneously to expel any gas present in thesecond chambers of the compression cylinders into rough vacuum chambersor ambient or a recycling facility.

The embodiments in FIGS. 1, 2, 8, and 10 show one condensation cylinder,but any number of additional condensation cylinders may be used toobtain the required pressure in the enclosed rough vacuum chamber, aswell as actuate the compression cylinders. Any number of additionalcompression cylinders may be used in FIGS. 8, and 10 to obtain therequired pressure in the RV and/or HV chambers.

The tasks in the process for driving compression cylinders are differentfrom the tasks in the process of generating vacuum to directly evacuatean enclosed volume, except for the first 5 tasks. These 5 tasks are nowlabeled as tasks 1* to 5*.

The process could then continue by inserting a first quantity of the hotwater into the wall channels of the condensation cylinder to repel thecold water in the channel and heat the cylinder (task 6*).

The process could then continue by inserting a second quantity of thesteam into the second chamber of the condensation cylinder (task 7*).

The process could then continue by moving the piston inside thecondensation cylinder, under the action of the second quantity of steamand rough vacuum in the first chamber cylinder, to increase the volumeof the second chamber and reduce the volume of the first chamber (task8*). The rods also move the pistons of the compression cylinders throughmechanical couplings.

The process could then continue by opening the outlet valve of the firstchamber of the condensation cylinder to expel any condensate presentwithin the chamber when the pressure reaches ambient pressure such as 1atm (task 9*). The outlet valve is closed when the piston reaches theend of the cylinder.

The process could then continue by moving the pistons of the compressioncylinders, under the action of the pistons of the condensation cylinder,to increase the volumes of their first chambers and reduce the volumesof their second chambers (task 10*). The valves to the vacuum chamberare opened to receive gas into the first chambers of the compressioncylinder. The outlet valves are opened to expel gas in the secondchamber of the compression cylinder into the rough vacuum chamber (forhigh vacuum generation) or into ambient or a recycling facility (forrough vacuum generation).

The process could then continue by blocking the steam flow into thesecond chamber of the condensation cylinder and inserting a secondquantity of the cold water into the wall channels of the condensationcylinder to repel the hot water in the channel to condense substantiallythe second quantity of steam in the second chamber of the condensationcylinder (task 11*).

The process could then continue by inserting a second quantity of thehot water into the wall channels of the condensation cylinder to repelthe cold water in the channel and heat the cylinder (task 12*).

The process could then continue by moving the steam valve to insert athird quantity of steam into the first chamber of the condensationcylinder (task 12*). The third quantity of steam and rough vacuum in thesecond chamber of the condensation cylinder moves the piston to increasethe volume of the first chamber and reduce the volume of the secondchamber; the rods also move the pistons of the compression cylindersthrough mechanical couplings in another direction.

The process could then continue by moving the pistons of the compressioncylinders to increase the volume of their second chambers and reduce thevolume of their first chambers (task 13*). The valves to the vacuumchamber are opened to receive gas in the second chambers of thecompression cylinder. The outlet valves are opened to expel gas in thefirst chambers of the compression cylinder into the rough vacuum chamber(for high vacuum generation) or into ambient or a recycling facility(for rough vacuum generation).

The process could then continue by opening the outlet valve of thesecond chamber of the condensation cylinder to expel any condensatepresent within the chamber (task 14*), when the pressure in the secondchamber of condensation cylinder reaches 1 atm. As the second actioncompletes, the cycle of dual-action completes.

In this manner, a steam is introduced into an enclosed chamber ofcondensation cylinder and is then cooled to induce condensation of thesteam. A dual-action piston-cylinder system produces piston movementwith steam and vacuum generated by condensation and rod of the pistonactuate the compression cylinders. In this manner, a multi-level vacuumgeneration system with reduced complexity and energy cost isestablished.

While at least one example embodiment has been presented in theforegoing detailed description, it should be appreciated that a vastnumber of variations exist. It should also be appreciated that theexample embodiment or embodiments described herein are not intended tolimit the scope, applicability, or configuration of the subject matterin any way. Rather, the foregoing detailed description will providethose skilled in the art with a convenient road map for implementing thedescribed embodiment or embodiments. It should be understood thatvarious changes can be made in the function and arrangement of elementswithout departing from the scope defined by the claims, which includesknown equivalents and foreseeable equivalents at the time of filing thispatent application.

The above description refers to elements, nodes, or features being“connected” or “coupled” together. As used herein, unless expresslystated otherwise, “connected” means that one element/node/feature isdirectly joined to (or directly communicates with) anotherelement/node/feature, and not necessarily mechanically. Likewise, unlessexpressly stated otherwise, “coupled” means that oneelement/node/feature is directly or indirectly joined to (or directly orindirectly communicates with) another element/node/feature, and notnecessarily mechanically. Thus, although FIGS. 1-10 depict examplearrangements of elements, additional intervening elements, devices,features, or components may be present in an embodiment of thedisclosure.

The above description refers to water and its vapor form as the workingsubstance in the condensation cylinder and the operation is based on thevapor-to-liquid phase change of the steam. Many other substances withsuitable vapor-to-liquid phase change temperature and pressure can alsobe used as the working media in the systems of the present disclosure.

Terms and phrases used in this document, and variations thereof, unlessotherwise expressly stated, should be construed as open ended as opposedto limiting. As examples of the foregoing: the term “including” shouldbe read as meaning “including, without limitation” or the like; the term“example” is used to provide exemplary instances of the item indiscussion, not an exhaustive or limiting list thereof; and adjectivessuch as “conventional,” “traditional,” “normal,” “standard,” “known” andterms of similar meaning should not be construed as limiting the itemdescribed to a given time period or to an item available as of a giventime, but instead should be read to encompass conventional, traditional,normal, or standard technologies that may be available or known now orat any time in the future.

Likewise, a group of items linked with the conjunction “and” should notbe read as requiring that each and every one of those items be presentin the grouping, but rather should be read as “and/or” unless expresslystated otherwise. Similarly, a group of items linked with theconjunction “or” should not be read as requiring mutual exclusivityamong that group, but rather should also be read as “and/or” unlessexpressly stated otherwise. Furthermore, although items, elements orcomponents of the disclosure may be described or claimed in thesingular, the plural is contemplated to be within the scope thereofunless limitation to the singular is explicitly stated. The presence ofbroadening words and phrases such as “one or more,” “at least,” “but notlimited to” or other like phrases in some instances shall not be read tomean that the narrower case is intended or required in instances wheresuch broadening phrases may be absent.

As used herein, unless expressly stated otherwise, “operable” means ableto be used, fit or ready for use or service, usable for a specificpurpose, and capable of performing a recited or desired functiondescribed herein. In relation to systems and devices, the term“operable” means the system and/or the device is fully functional andcalibrated, comprises elements for, and meets applicable operabilityrequirements to perform a recited function when activated. In relationto systems and circuits, the term “operable” means the system and/or thecircuit is fully functional and calibrated, comprises logic for, andmeets applicable operability requirements to perform a recited functionwhen activated.

A method is provided for reducing pressure to a rough or high vacuumstate in an enclosed volume or an open flow system with apiston-cylinder condensation and compression through a dual-actioncycle. In one embodiment, the method includes inserting a first quantityof steam into a first chamber of a condensation cylinder, condensing thefirst quantity of steam in the first chamber, and compressing a firstquantity of gas in the compression cylinder from an enclosed vacuumvolume or an open flow system, inserting a second quantity of steam intoa second chamber of a condensation cylinder, condensing the secondquantity of steam in the second chamber, and compressing a secondquantity of gas in the compression cylinder from an enclosed vacuumvolume or an open flow system.

The method comprises performing heat exchange with the steam inside acylinder with embedded channels in its heat conducting wall along itsaxis and/or with atomizing spray. The method also includes a free-movingpiston separating two chambers of variable volumes within thecondensation cylinder, a pressurized steam (steam at elevatedtemperature) moves the piston to increase the volume of one chamberwhile decreasing the volume of the other chamber, and external actuationis not required for the movement of the piston in the condensationcylinder. The method includes moving a three-position steam valve tosubstantially fill the first chamber with the first quantity of steam.The method includes substantially expelling the first quantity of gasand water condensate through a first outlet from the second chamber bythe piston movement during an insertion of the first quantity of steaminto the second chamber. The method comprises moving the three-positionsteam valve to block a first steam flow of the first quantity of steaminto the first chamber.

The method comprises opening the cold water valve to allow the flow ofthe first quantity of cold water from the water chiller to cool thecylinder and condense the first quantity of steam in the first chamber.The method comprises moving the three-position steam valve tosubstantially fill a second chamber with a second quantity of steam. Themethod includes substantially expelling the second quantity of gas andwater condensate through a second outlet from the first chamber by thepiston movement during an insertion of the second quantity of steam intothe second chamber.

The method includes moving the three-position steam valve to block thesecond steam flow of the second quantity of steam into the secondchamber. The method includes condensing the second quantity of steam inthe second chamber, thereby starting the next cycle of the dual-action.The method provides significant cost saving on energy consumption due tomore efficient use of steam as well as time saving in gas expellingprocess.

A rough vacuum generation system comprises a condensation cylinderoperable to receive alternatively a first quantity and a second quantityof steam into its two chambers, a plurality of channels in the cylinderwall operable to allow flows of cold water through them to perform heatexchange with the content inside the cylinder, a plurality of atomizingspray nuzzles at the ends of the cylinder operable to spray cold waterthrough them to perform heat exchange with the content inside thecylinder, a steam generator to provide the first and the secondquantities of steam, and a water chiller to condense the first andsecond quantities of steam such that a vapor-to-liquid phase changereduces a pressure in the two chambers alternatively to provide a roughvacuum state.

A multi-level vacuum storage comprises at least one rough vacuum chamberand one high vacuum chamber, operable to interact with a rough vacuumcompressor and a high vacuum compressor to attain and maintain propervacuum states.

A vacuum generation system comprises a compression cylinder operable toreceive alternatively a first quantity and a second quantity of gas froma vacuum chamber into its two chambers, a piston and rod operable tomove insider the compression cylinder under the force exerted by thepiston rods of the condensation cylinder.

The system includes a three-position steam valve coupled to thecondensation cylinder and operable to regulate the first and the secondquantities of steam. The three-position steam valve may be replaced by apair of two-position steam valves, operable to open/close alternately.The system includes enclosed multi-level chambers or open flow systemscoupled to the valves and operable to provide a reduced gas pressure inthe enclosed chambers or open flow systems. The system includes valvescoupled to the compression cylinder and operable to reduce pressure inthe vacuum chamber or open flow system.

The system further includes a controller operable to control the steamvalve, gas valve, cold water valve and outlet valves. The cold water maybe replaced by other coolants as condenser, which however requiresseparate channels in the cylinder wall.

The water and steam could be the working medium and recyclable is veryenvironment friendly. Other condensable gases may be used to replacewater and steam to reach lower pressure limits. The capacity andefficiency of the process depend mainly on the heat transfer rate ofcooling and condensation temperature, and nearly independent of volumeand shape of the cylinder, thereby ensuring its scalability. Thedisclosed system involves limited number of moving parts and mostly inlinear motions, and hence generates little flow-induced noise. Theelectricity usage is mainly for the associated control needs, cold waterpumping and chiller operation, compared to the huge demand of electricpower in existing commercial vacuum technologies.

Use of vacuum as an industrial process technology is largely driven bythe electronics industry. There are also many chemical, petrochemicaland pharmaceutical applications, such as evaporation, condensation,freeze-drying, distillation, deodorization, degassing, absorption, andimpregnation. Vacuum evaporation and distillation is now also used inwastewater treatment technology, resulting in a dramatic reduction inthe volume of liquid waste, which allows effluents that cannot viably betreated using physicochemical or biological techniques to be treated ina clean, efficient, safe and compact manner.

Vacuum-assisted pneumatic conveying, also known as negative-pressureconveying, has been widely used for transport of particulate (such asrice, beans, pulverized coal, granular ores or chemicals) via pipelines.The vacuum-assisted pneumatic conveying is extremely useful in thetransport of toxic and hazardous materials since this type of conveyancenot only provides dust-free feeding but also prevents the escape ofsolids through leakage (if any) in the pipeline. In addition, vacuumcleaning at industrial sites constantly requires large-scaled low-costvacuum technology.

Another application involves high-volume aerosol filtration technology.The high efficient aerosol filtration system, such as High-EfficiencyParticulate Arrestance (HEPA) filter for removal of ultrafineparticulates such as PM2.5, typically require a high pressure head toovercome the high pressure drop that increases in a quadratic functionwith the increase in flowrate. This disclosed vacuum technology providesan ideal flow driving solution, which is low energy cost, high pressuredifference and low noise, to the ever-growing needs of filtrations ofultrafine aerosols.

Current vacuum technology consists of positive displacement pumps,momentum transfer pumps, and entrapment pumps to generatesub-atmospheric pressure at different vacuum levels. Pumping and pumpingservices comprise about two-thirds of the market. The pump shaft speedhas steadily increased to meet the greater demand on capacity. There is,however, a fundamental limit to the maximum speed that can be achievedby a particular pumping technology, since it takes time to make a gas toflow into a space, especially at a low pressure. Pumps typically arenoisy and it is very costly to apply them to very large enclosed volumesdue to the energy consumption for such a facility. The system may bedeveloped to replace many, if not most, of the existing vacuum pumps forobtaining a rough and high vacuum.

While exemplary embodiments have been described herein, it is expresslynoted that these embodiments should not be construed as limiting, butrather that additions and modifications to what is expressly describedherein also are included within the scope of the invention. Moreover, itis to be understood that the features of the various embodimentsdescribed herein are not mutually exclusive and can exist in variouscombinations and permutations, even if such combinations or permutationsare not made express herein, without departing from the spirit and scopeof the invention. 16-034

The invention claimed is:
 1. A method for reducing pressure to a vacuumstate in an enclosed volume or an open flow system, comprising:inserting a first quantity of steam into a first chamber of a cylinder;condensing the first quantity of steam in the first chamber; inserting asecond quantity of steam into a second chamber of the cylinder, thefirst and second chambers separated by a first movable piston and a heatexchanger; condensing the second quantity of steam in the secondchamber; and moving the first piston with the first and the secondquantities of steam to fill the first and the second chambers whileexpelling gaseous content and condensate out of the first and the secondchambers, respectively, to achieve a vacuum generation.
 2. The method ofclaim 1, further includes extracting a first quantity of gas from anenclosed volume or an open flow system into the first chamber, andwherein the heat exchanger is a wall-imbedded heat exchanger disposedwithin the cylinder.
 3. The method of claim 2, further includesextracting a second quantity of gas from the enclosed volume or the openflow system into the second chamber, and repeating a dual action cycleby the inserting and the condensing of the first and the secondquantities of steam in the first and the second chambers to achieve asustained vacuum generation.
 4. The method of claim 1, wherein areduction of pressure is generated with the first and the secondchambers that create a combination of a condensation cylinder and avacuum compression cylinder.
 5. The method of claim 4, wherein thecondensing of the first and the second quantity of steam is through theheat exchanger in the first and the second chamber of the condensationcylinder, respectively.
 6. The method of claim 5, further includesmoving the first piston and a first rod in the cylinder by a combinationof a rough vacuum in the first chamber of the cylinder and steam in thesecond chamber of the cylinder.
 7. The method of claim 6, furtherincludes moving a second piston in the cylinder by a second rod coupledto the first rod of the cylinder.
 8. The method of claim 7, furtherincludes inserting a first quantity of gas from a vacuum chamber intothe first chamber of the cylinder.
 9. The method of claim 8, furtherincludes inserting a third quantity of steam into the first chamber ofthe cylinder.
 10. The method of claim 9, further includes moving thefirst piston and the first rod in the cylinder by a combination of arough vacuum in the second chamber of the cylinder and the steam in thefirst chamber of the cylinder.
 11. The method of claim 10, furtherincludes moving the second piston in the cylinder by the second rodcoupled to the first rod of the cylinder.
 12. The method of claim 11,further includes compressing the first quantity of gas in the firstchamber of a vacuum compression cylinder into a rough vacuum chamber.13. The method of claim 12, further includes inserting a second quantityof gas from a high vacuum chamber into the second chamber of the vacuumcompression cylinder.
 14. A vacuum generation system comprising: acylinder including two chambers and a cylinder wall, the cylinderoperable to receive alternatively a first quantity and a second quantityof steam into the two chambers; a plurality of channels in the cylinderwall operable to allow flows of hot and cold water through the channelsto perform heat exchange with content inside the cylinder; a steam andhot water generator to heat the cylinder wall and to provide the firstand the second quantities of steam; and a heat exchanger for the firstand second quantities of steam to condense for a vapor-to-liquid phasechange that reduces a pressure in the two chambers and provides areduced pressure.
 15. The system of claim 14, further including a waterchiller in communication with the heat exchanger to condense the firstand second quantities of steam.
 16. The system of claim 14, furtherincluding a multi-level vacuum storage system.
 17. The system of claim16, wherein the multi-level vacuum storage system further includes, arough vacuum chamber for rough vacuum storage evacuated by acondensation based vacuum generator or a pump; and a high vacuum chamberdisposed inside the rough vacuum chamber for high vacuum storageevacuated by the condensation based vacuum generator or the pump.
 18. Amulti-level vacuum generation system comprising: a condensation cylinderoperable to receive alternatively a first quantity and a second quantityof steam into at least two chambers; a plurality of channels in thecondensation cylinder wall for flow of cold water therethrough toperform heat exchange with a content inside the condensation cylinder; aplurality of atomizing spray nozzles for cooling the content inside thecondensation cylinder; and a steam generator providing the first and thesecond quantities of steam and a third quantity of steam, a waterchiller to condense the first and the second quantities of steam for avapor-to-liquid phase change that reduces a pressure in the two chambersalternatively to provide a rough vacuum; a compression cylinder forreceiving alternatively a first quantity and a second quantity of gasfrom a vacuum chamber into at least two chambers of the compressioncylinder; a first rod of the compression cylinder coupled to a secondrod of the condensation cylinder; and a first piston in the compressioncylinder for compressing the first and the second quantities of gas intoa rough vacuum chamber for high vacuum generation or into ambient or arecycling facility for rough vacuum generation.
 19. The system of claim18, further including a multi-level vacuum storage system wherein therough vacuum chamber for rough vacuum storage is evacuated by acondensation based vacuum generator or a pump.
 20. The system of claim19, further including a high vacuum chamber disposed inside the roughvacuum chamber for high vacuum storage that is evacuated by thecondensation based vacuum generator or the pump.